i've an 84z original carbed, I put in a b&m mega shifter the other day, now when I rewired the neutral safety and reverse to the new switchs that came with the shifter I noticed after everything was adjusted and properly installed the factory tach was pegged to the max. I had the car off during the simple wiring process and had not even took the car out for a road test, any reason for a tach to do this, the shifter and wiring shouldnt have had an effect on it that Im aware of. This car is not ecm controled and the tach worked great and I retain all my other gages and what not.

 

my car did that once. i went to turn it over and it went up and stayed half way so i turned it off and tryed starting again and it eventually got pegged. sure my battery was low so it took alittle while to start. anyway the way to fix it is to take off the 2 plastic covers infront of the gauges and just flip it back to zero. my still worked untill i swapped all autometer gauges in.

 

well I'll try that, its simple and fast but if it doesnt cut the mustard I guess we'll have ta go another route